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Re:SSD will fail at 40k power-on hours (2021) by dredmorbius on Sunday July 10, 2022 @09:29PM (#32051185)
Within an earlier thread "Tell HN: HN Moved from M5 to AWS", there's an excellent comment by loxias about risk diversification across multiple factors. Well worth reading:

https://news.ycombinator.com/item?id=32031655

I've increasingly come to view systems operations / SRE as a risk management exercise, where the goal is to reduce the odds of a catastrophic failure. Total system outage is one level, unrecoverable total system outage is even worse.

Having multiple redundant backups / storage systems, in different locations, with different vendor hardware / stacks, all helps reduce risk of a single-factor outage. Though complexity risk is its own issue.

Re:SSD will fail at 40k power-on hours (2021) by kqr on Monday July 11, 2022 @12:49AM (#32052327)
> I've increasingly come to view systems operations / SRE as a risk management exercise, where the goal is to reduce the odds of a catastrophic failure.

s/reduce/find an appropriate level for/

It's a common misconception that risk management and risk reduction are synonyms. Risk management is about finding the right level of risk given external factors. Sometimes that means maintaining the current level of risk or even increasing it in favour of other properties.

Re:SSD will fail at 40k power-on hours (2021) by dredmorbius on Monday July 11, 2022 @02:25AM (#32052870)
My point is that risk is central to systems management. If you look at earlier standard texts on the subject, e.g., Nemeth or Frisch, the concept of risk is all but entirely missing. I've numberous disagreements with Google, but one place where I agree is that the term SRE, systems reliability engineer, puts the notion of managing for stability front and centre, and inherently acknowledges the principle of risk. I've since heard from others that this is in fact how the practice is presented and taught there.

Quibbling over whether the proper term is risk management or risk reduction rather spectacularly misses the forest for the trees.

Re:SSD will fail at 40k power-on hours (2021) by mst on Monday July 11, 2022 @04:50AM (#32053730)
A friend of mine who was once at Google mentioned that in a meeting once their SRE group was told by their senior manager roughly "you've broken stuff in $time_period far less than your outage budget, and that probably means you should've been rolling out features faster".

Risk -levels- are a choice and also a trade-off.

Re:SSD will fail at 40k power-on hours (2021) by kqr on Monday July 11, 2022 @04:36AM (#32053654)
Okay, fair enough. To me, the risk involvement is so obvious (to any serious business function!) that I find the management/reduction distinction a more important point. But I can see it your way too.
Re:SSD will fail at 40k power-on hours (2021) by dredmorbius on Monday July 11, 2022 @04:57AM (#32053760)
Thanks.

I don't know how long you've been in the business, but the change seems a relatively recent one, one that wasn't manifestly obvious to me, and one that has pretty much always seemed difficult to communicate to management.

Whether that's because business management is often about ignoring risks or treating it as inconvenient, or if I've just had a long string of bad bosses, I'm not sure.

I did make a point of looking through several of the books that were formative for me (mostly 1990s and 2000s publication dates), and there's little addressing the point. Limonchelli's book on time management for sysadmins was a notable departure from the standard when it came out, in 2008. I'd say that marked the shift toward structured and process-oriented practices.

That was about the time of the transition from "pets" to "cattle" (focus on individual servers vs. groups / farms), but pre-dates the cloud transition.

Re:SSD will fail at 40k power-on hours (2021) by kqr on Monday July 11, 2022 @05:54AM (#32054122)
You know what? You're right again!

The stuff I've read that touches on this idea is almost all from 2006 and onwards, mainly 2010s. The earliest example is a bit of an outlier: Douglas Hubbard's 1985 How to Measure Anything -- but it's also only tangentially related.

The other real exceptions are books on statistics (where the idea of risk management -- at least in my collection -- seems to have gotten popular in the 1950s, probably as a result of the second World war) and financial risk management (which seems to really have taken off in the 1980s, probably in conjunction with options becoming a thing.) Statisticians and finance people (and by extension e.g. poker and bridge players) have known this stuff for a while.

Of course, hydrologists have been doing this stuff since the early 1900s at least, but extreme value theory has always been a kind of niche so I'm not sure I should count that.

----

That said, I did mention it was obvious to me. I still find it hard to convince management and colleagues of its importance...

Re:SSD will fail at 40k power-on hours (2021) by no-s on Monday July 11, 2022 @11:28AM (#32057417)
> The stuff I've read that touches on this idea is almost all from 2006 and onwards, mainly 2010s. The earliest example is a bit of an outlier: Douglas Hubbard's 1985 How to Measure Anything -- but it's also only tangentially related.

I didn’t keep good track of such things but a lot of my early reading in the 70’s was in operations research and decision support systems, mostly sort of what we call operational analytics these days with a big helping of statistical process control too. World War 2 logistics practices and ‘50s and ‘60s “scientific management” fads generated a lot of material, some insightful. Many medium-sized businesses could afford significant R&D then, so you’ll find e.g. furniture factories developing their own computer systems from PCBs to custom ASIC components, just to manage statistical process control and decision support systems.

> That said, I did mention it was obvious to me. I still find it hard to convince management and colleagues of its importance...

I think the reason I keep having to justify this every few years is the tendency towards abstractions in management which try to simplify things into “anecdotal analytics”, e.g. preferring a persuasive narrative over reality...for a good cynical perspective from the ‘50s I recommend C.M. Kornbluth’s “The Marching Morons” (<https://en.wikipedia.org/wiki/The_Marching_Morons>).

Re:SSD will fail at 40k power-on hours (2021) by no-s on Monday July 11, 2022 @10:47AM (#32056877)
> It's a common misconception that risk management and risk reduction are synonyms. Risk management is about finding the right level of risk given external factors. Sometimes that means maintaining the current level of risk or even increasing it in favour of other properties.

What’s funny is I seem to have to explain this to senior management anew every 6-7 years. I know they teach it in management school, but it in the real world somehow people fall into the false equivalence when they get promoted. Often they adopt a cartoonish view of things because they can’t get the quantitative signals and everything decision effectively reduces to what I ironically term as anecdotal analytics.

I have this amusing heuristic for risk acceptance which I often use to help people approach decisions: you should kick the decision up to someone with higher authority if your signing authority is less than: risk coefficient times quantified exposure, less mitigation cost where mitigation is within signing authority AND/OR budgeted and authorized spend. I like to view mitigation and opportunity cost/benefit in a similar way so I have some idea of equivalences when evaluating tradeoffs.

It’s not original with me, I must have lifted it from some decades-past HBR article or 60’s rant on quantitative business management.

I could rant on various aspects of risk management application all day, thank goodness I've managed to quit before I really got started sharing...in my experience it’s been very helpful when applied in real world engineering implementations.

Re:SSD will fail at 40k power-on hours (2021) by gfrff on Monday July 11, 2022 @02:31AM (#32052900)
One of the advantages startups have is higher risk tolerance than branded megacorporations. Data, customers, brand, employees, law suits, or cynically, human lives.
Re:SSD will fail at 40k power-on hours (2021) by dredmorbius on Monday July 11, 2022 @05:00AM (#32053782)
The risk-tolerance of startups is illusory.

The risk is being managed at the VC/investor level, by diversifying investment bets over numerous early ventures.

The death of any one of those isn't a concern for the VC, if the portfolio performance is sufficient. Of course, for the individual venture and employees, that risk is disaggregated.

More rigorous systems practices are seen as an impediment to early growth with any potential problems either something that can be ironed out later, or simply a post-liquidation concern that doesn't factor into the investors' interests at all.

Re:SSD will fail at 40k power-on hours (2021) by gfrff on Tuesday July 12, 2022 @01:50AM (#32066131)
The risk tolerance is there result of not potentially taking out $1T of additional value if you f-- up a small project at a mega corporation.

At a mega corporation, you can't take risks which make complete sense for the project you're on independent of uncapped liability for the mothership.

There are misalignments like the one you describe but that's not what I'm talking about.

Re:SSD will fail at 40k power-on hours (2021) by no-s on Monday July 11, 2022 @10:49AM (#32056915)
> Total system outage is one level, unrecoverable total system outage is even worse.

Ha, I used to suggest people consider “total failure of business” in exposure quantification...